YCEI hosts side event exploring the air quality-climate change nexus at the UN Climate Conference in Doha, Qatar

The Yale Climate and Energy Institute (YCEI) organized and hosted an interdisciplinary panel of climate scientists, policymakers, and practitioners at the UN Climate Conference held in Doha, Qatar last month to discuss the intersection of air quality and climate change science and policy. While negotiators from nearly 200 countries spent two weeks hammering out political nuances and technical details of climate agreements, one aspect that was notably absent was discussion of the relationship between greenhouse gas (GHGs) and aerosol emissions. In particular, the effects of short-lived climate pollutants (SLCPs) on temperature, and how SLCPs such as black carbon can be addressed to help close the gap needed to contain global warming.

Moderated by Jean-Pascal van Ypersele, Vice-Chair of the Intergovernmental Panel for Climate Change (IPCC) and a climatologist, the panel featured perspectives to explain the relationship between aerosols and climate change, as well as on-the-ground examples of how countries are working to bridge the gap between climate change and air quality. Rajendra K. Pachauri, Advisor to the YCEI and IPCC chair, provided opening remarks via video message and said there is considerable need for research of air quality impacts, particularly at the local level. He asserted that most climate mitigation actions have co-benefits of improving air quality, although all of the mechanisms and feedback loops are not yet fully understood.

Dr. Pachauri’s remarks laid the foundation for the first two presentations by YCEI affiliates, who provided introductions to the most recent scientific research linking climate change and aerosols. Trude Storelvmo, an assistant professor in the Department of Geology and Geophysics at Yale University, established that aerosols in the atmosphere affect how much heat is absorbed by the atmosphere versus how much is reflected back into space, although the exact quantities are unknown and subject to a considerable margin of error. She emphasized that the strength of a cooling affect resulting from aerosols (such as sulfates) almost counterbalances the warming effects of GHGs. However, aerosol emissions are being drastically reduced worldwide because of air quality concerns, as they have both human health and ecosystem impacts, and in turn accelerate global warming.

Thomas Leirvik, a YCEI Post-doctoral associate, followed Dr. Storelvmo’s talk with a presentation on research that models the relationship between GHG emissions and atmospheric aerosols. Adding to Dr. Storelvmo’s remarks, he noted that solar radiation also has increased due to air pollution reduction since the 1990s. Current climate models underestimate these trends in solar radiation and therefore underestimate temperature increases.

Switching gears from science to policy, Nick Nuttall, Communications Director of the UN Environment Programme (UNEP), introduced a new initiative between 25 countries to collaborate to reduce SLCPs called the Climate and Clean Air Coalition (CCAC). Speaking with great energy, Mr. Nuttall spoke about how countries aim to address SLCPs, through efforts to reduce methane emission from landfills, hydrofluorocarbons, heavy-duty vehicles, brick production, and oil and gas flaring. He not only highlighted the health and local benefits to communities in addressing these areas, but also the increases to food production due to reductions in ground-level ozone. The CCAC was noted as a “rare note” of harmony between countries at the conference in Doha. The United States is also a founding member of the CCAC; however, notably absent from the Coalition are big emitters and emerging economies, including China, India, and Brazil. It remains to be seen if without these major developing countries, whether the CCAC will have as large of a global impact as intended. Nonetheless, initiatives like the CCAC, particularly amidst so much inaction and lack of agreement, have formed and are moving forward to make efforts where science clearly establishes the need for action.

Speaking of China, the climate heavyweight at the negotiations, Kevin Tu of the Carnegie Endowment for International Peace, presented a case study on what China can do to simultaneously address air quality and climate change. Because 70 percent of China’s energy mix is coal-based, air pollution and climate change impacts are quite severe as the country continues to industrialize at breakneck speeds. Particularly in the wake of the Fukushima-Daiichi nuclear disaster that affected Japan in 2011, China has slowed down its construction of nuclear power plants, leaving a sizable challenge for the country to meet growing energy demand. One of the proposals Mr. Tu made was for smaller coalitions of countries – China, the US, Russia, and the EU (or CURE) – to work together to establish low-carbon initiatives together, considering energy consumption and carbon emissions of this bloc of countries is expected to continuously represent more than half of the global total for decades to come.

Finally, Ainsley Lloyd of the Yale Center for Environmental Law and Policy (YCELP), who courageously stood in for me due a severe case of laryngitis that left me literally voiceless at the climate negotiations, presented a new effort that YCELP is spearheading to improve global air quality indicators. “Towards the Next Generation of Air Quality Indicators” is an effort that convenes leading scientists on particulate matter, mercury, persistent organic pollutants, and ozone to identify current measurement gaps and future investments needed to develop more policy-relevant indicators so that decision-makers can make better decisions to address air pollution.

The presentations on the panel were followed by a panel discussion that delved deeper into the science and policy connections between climate change and air quality. Dr. Storvelmo, while applauding the efforts of the freshly-launched CCAC, cautioned that the attention on black carbon reductions could possible detract attention away from CO2 reductions, which is absolutely necessary to address climate change in the long-term. Mr. Nuttall countered by saying that countries should be looking at the co-benefits of addressing both air quality and climate change together, and that the efforts proposed by the CCAC should be additional to CO2 reductions.

The good news is that the conversation in Doha will be continued Feb. 7-8 in New Haven, CT at the Fourth Annual Symposium of the Yale Climate and Energy Congress, the student-run group of the YCEI. The symposium will discuss, “The Atmospheric Science-Climate Policy Frontier,” and will feature scientists such as Mark Jacobson, Director of the Atmosphere and Energy Program at Stanford University, as well as policy practitioners such as Daniel C. Esty, Commissioner of Connecticut’s Department of Energy and Environmental Protection. We hope that you will be able to join us to continue the dialogue from Doha.

Parts of this blog drew from the International Institute for Sustainable Development’s (IISD) Earth Negotiations Bulletin - On the Side. YCEI COP-18 fellow, William Miao, a Masters of Environmental Management (MEM’14) candidate at the Yale School of Forestry and Environmental Studies, contributed to this blog.